This invention relates generally to digital processing systems and more particularly to an apparatus for automatically processing both encoded and unencoded data.
Optical storage media, such as CD, CD-ROM, CDR, CDR/W, DVD, and MD, have been used for a number of years by the entertainment industry as a mechanism for delivering products, such as digitized movies and music, to consumers. With optical media, it is possible to deliver vast amounts of data (for example, a typical compact disk (CD) has a storage capacity of approximately 660 megabytes) to consumers at a relatively low cost.
In recent years, the Internet has begun replacing optical media as the delivery mechanism of choice for digitally-based products. With the Internet, it is no longer necessary to deliver a physical disk to a consumer; rather, the consumer can directly download the product via the Internet onto his/her own storage device, which may, for example, be a hard disk on a computer or an optical storage disk (such as a CDR or CDR/W disk). Once downloaded, the digitally-based product may be rendered or played using a rendering device, such as a CD player, a computer, or some other device. Because the Internet enables direct downloads, delivery of the product is typically faster, and consumer gratification is much more immediate.
Downloading does not come without its problems, however. One major problem is the significant length of time needed to download a file. As an example, a 4-minute song, which usually is approximately 40MB in size, requires over three hours to download using a 28.8 kbps modem. For most consumers, this is an intolerably long period of time.
To alleviate this problem, some mechanisms have been developed to reduce the size of files prior to download, thereby reducing the amount of time needed to download the files. In the audio data file arena, one such mechanism is the MP3 mechanism developed by the Motion Picture Experts Group (MPEG). MP3, also known as MPEG Audio Layer-3, uses a perceptual noise shaping coding scheme to reduce the number of bits needed to represent an audio file. With MP3, it is possible to reduce the size of an audio file by a factor of ten to twelve so that a song that formerly required hours to download now takes only minutes to acquire.
A point to note regarding MP3 is that, although it does significantly reduce the size of an audio file, it is more an encoding scheme than a compression algorithm, and as with any encoding scheme, it requires a decoder on the receiving end to render the encoded file. That is, the consumer downloading an MP3 file needs to have an MP3 decoder in order to render or play the downloaded file. Typically, an MP3 decoder takes the form of a decoder program on a computer. To render an MP3 file, a consumer executes the decoder program and instructs it to decode a file stored in memory or on a hard drive. Once decoded, the audio file is rendered to the consumer via the computer""s sound system. Dedicated MP3 players have also been developed. This type of player interfaces with a memory module, such as a flash memory card, to access an MP3 file stored thereon, and then decodes and plays the file.
Whatever form an MP3 decoder takes, one point is clear: an MP3 file has a very different format than a regular audio data file. Thus, an MP3 decoder cannot render a regular audio data file, and a regular audio data file rendering mechanism (such as a CD player) cannot render an MP3 file. As a result, in order to render both types of files, a consumer needs to have two different sets of equipment, one for rendering MP3 files and another for rendering unencoded files. This imposes additional cost on the consumer, which in turn, encourages the consumer to choose between the two formats and to adopt only one. This is an undesirable result. What is needed instead is a mechanism that can automatically detect and render both types of files.
The present invention provides an apparatus for automatically rendering both encoded and unencoded data files. According to one embodiment, the present invention comprises a data processor and a decoder. The data processor receives a set of input data from a storage medium, such as an optical storage medium, and determines whether the set of input data is encoded or unencoded.
If the input data is encoded (for example, in accordance with the MP3 encoding scheme), then the data processor provides to the decoder a set of encoded data, and generates an indication signal to cause the decoder to be activated. In response, the decoder decodes the set of encoded data and provides as output a set of decoded data. This decoded data may then be provided to a signal transport mechanism, such as a digital signal bus, to be rendered by a digital device such as a computer, or to a digital-to-analog converter which converts the decoded data into analog signals for driving an analog device, such as a speaker. In either case, the encoded data is automatically transformed to enable it to be successfully rendered.
On the other hand, if the data processor determines that the input data is unencoded (for example, has a standard audio file format, such as WAVE), then the data processor processes the set of input data to derive a set of processed data, and provides this set of processed data at its output. No indication signal is generated; thus, the decoder is not activated. The processed data may then be provided to a signal transport mechanism, such as a digital signal bus, to be rendered by a digital device such as a computer, or to a digital-to-analog converter which converts the processed data into analog signals for driving an analog device, such as a speaker. The unencoded data is thus processed and rendered.
As disclosed above, the present invention is capable of processing both encoded and unencoded data from a storage medium. Thus, With the present invention, a user is no longer required to have two different devices in order to render both types of data. Instead, the single apparatus of the present invention may be used. As a result, the user is free to adopt both the encoded and unencoded data formats. Further, the user may use the same apparatus to render both data formats. This is a significant improvement over the prior art.